On 10-09-02 22:43, Wengang Wang wrote: > I am taking back this patch since where is another such violation in
Sorry for the typo. s/where/there regards, wengang. > dlm_flush_asts(). > > I will try to fix the both in one combination. > > regards, > wengang. > > On 10-09-02 21:17, Wengang Wang wrote: > > /* > > * > > * spinlock lock ordering: if multiple locks are needed, obey this ordering: > > * dlm_domain_lock > > * struct dlm_ctxt->spinlock > > * struct dlm_lock_resource->spinlock > > * struct dlm_ctxt->master_lock > > * struct dlm_ctxt->ast_lock > > * dlm_master_list_entry->spinlock > > * dlm_lock->spinlock > > * > > */ > > > > There is a violation that locks on dlm_lock_resource->spinlock after locking > > on dlm_ctxt->ast_lock. The violation is not detected because so far there is > > only one place where both the two spinlock are taken at the same time. But > > it > > is a potential deadlock in future(when the two lock are taken all together > > in > > correct order). > > > > This patch fixes the problem by changing the calling order. > > > > Signed-off-by: Wengang Wang <[email protected]> > > --- > > fs/ocfs2/dlm/dlmthread.c | 6 +++--- > > 1 files changed, 3 insertions(+), 3 deletions(-) > > > > diff --git a/fs/ocfs2/dlm/dlmthread.c b/fs/ocfs2/dlm/dlmthread.c > > index 2211acf..676ff3e 100644 > > --- a/fs/ocfs2/dlm/dlmthread.c > > +++ b/fs/ocfs2/dlm/dlmthread.c > > @@ -671,8 +671,8 @@ static int dlm_thread(void *data) > > /* lockres can be re-dirtied/re-added to the > > * dirty_list in this gap, but that is ok */ > > > > - spin_lock(&dlm->ast_lock); > > spin_lock(&res->spinlock); > > + spin_lock(&dlm->ast_lock); > > if (res->owner != dlm->node_num) { > > __dlm_print_one_lock_resource(res); > > mlog(ML_ERROR, "inprog:%s, mig:%s, reco:%s, > > dirty:%s\n", > > @@ -691,8 +691,8 @@ static int dlm_thread(void *data) > > DLM_LOCK_RES_RECOVERING)) { > > /* move it to the tail and keep going */ > > res->state &= ~DLM_LOCK_RES_DIRTY; > > - spin_unlock(&res->spinlock); > > spin_unlock(&dlm->ast_lock); > > + spin_unlock(&res->spinlock); > > mlog(0, "delaying list shuffling for in-" > > "progress lockres %.*s, state=%d\n", > > res->lockname.len, res->lockname.name, > > @@ -713,8 +713,8 @@ static int dlm_thread(void *data) > > /* called while holding lockres lock */ > > dlm_shuffle_lists(dlm, res); > > res->state &= ~DLM_LOCK_RES_DIRTY; > > - spin_unlock(&res->spinlock); > > spin_unlock(&dlm->ast_lock); > > + spin_unlock(&res->spinlock); > > > > dlm_lockres_calc_usage(dlm, res); > > > > -- > > 1.7.2.2 > > > > > > _______________________________________________ > > Ocfs2-devel mailing list > > [email protected] > > http://oss.oracle.com/mailman/listinfo/ocfs2-devel _______________________________________________ Ocfs2-devel mailing list [email protected] http://oss.oracle.com/mailman/listinfo/ocfs2-devel
